Answer:
Explanation:
Firstly, when you measure the voltage across the battery, you get the emf,
E = 13.0 V
In order to proceed we have to assume that the voltmeter offers no loading effect, which is a valid assumption since it has a very high resistance.
Secondly, the wires must be uniform. So the resistance per unit length is constant (say z). Now, even though the ammeter has very little resistance it cannot be ignored as it must be of comparable value/magnitude when compared to the wires. This is can seen in the two cases when currents were measured. Following Ohm's law and the resistance of a length of wire being proportional to it's length, we should have gotten half the current when measuring with the 40 m wire with respect to the 20 m wire (
). But this is not the case.
Let the resistance of the ammeter be r
Hence, using Ohm's law we get the following 2 equations:
.......(1)
......(2)
Substituting the value of r from (2) in (1), we have,
which simplifying gives us, 
(which is our required solution)
putting the value of z in either (1) or (2) gives us, r = 0.5325 
Answer:
Sun
Explanation:
Sun Can Give Us Light Energy And It convert Into Heat Energy
Explanation:
Assuming a uniform mass, let's say ρ is the mass per area density.
ρ = M / (πR²)
Let's look at this as the difference of two disks, a large one and a small one.
The moment of inertia of the large disk is:
I = 1/2 MR²
The mass of the small disk is:
m = ρ πr²
m = M / (πR²) πr²
m = M (r/R)²
Using parallel axis theorem, the moment of inertia of the small disk is:
I = 1/2 mr² + md²
I = 1/2 M (r/R)² r² + M (r/R)² d²
I = 1/2 M (r²/R)² + M (rd/R)²
The total moment of inertia is:
I = 1/2 MR² − 1/2 M (r²/R)² − M (rd/R)²
Answer:
A) yes
Explanation:
First section of trip: 30 miles in 40 minutes
Second section of trip: 15 miles in 20 minutes
The formula for speed is distance over time 
Calculate the speeds for each section of the trip.
First:
k = d/t
k = 30miles/40minutes <= reduce fraction by 10 (30÷10 and 40÷10)
k = 3 miles / 4 minutes
Second:
k = d/t
k = 15miles/20minutes <= reduce fraction by 5 (15÷5 and 20÷5)
k = 3 miles / 4 minutes
Therefore there is a constant speed because both sections of the trip are driving at "3 miles / 4 minutes".
3 miles / 4 minutes can be also formatted as:
0.75 miles per minute.
